China's Growing Pollution Reaches U.S.

Researcher Steven S. Cliff displays a set of rotating drums that separate aerosols from the air at his monitoring site atop Mt. Tamalpais State Park, Calif., Thursday, July 20, 2006. On a mountaintop overlooking the Pacific Ocean, Cliff collects evidence of an industrial revolution taking place thousands of miles away. At an air monitoring station just north of San Francisco, Cliff measures particulate pollution carried across the Pacific from coal-fired power plants, smelting factories, dust storms and vehicle emissions in Asia, the bulk originating from China. (AP Photo/Eric Risberg) (Eric Risberg - AP)

MOUNT TAMALPAIS STATE PARK, Calif. -- On a mountaintop overlooking the Pacific Ocean, Steven Cliff collects evidence of an industrial revolution taking place thousands of miles away.

The tiny, airborne particles Cliff gathers at an air monitoring station just north of San Francisco drifted over the ocean from coal-fired power plants, smelters, dust storms and diesel trucks in China and other Asian countries.

Researchers say the environmental impact of China's breakneck economic growth is being felt well beyond its borders. They worry that as China consumes more fossil fuels to feed its energy-hungry economy, the U.S. could see a sharp increase in trans-Pacific pollution that could affect human health, worsen air quality and alter climate patterns.

"We're going to see increased particulate pollution from the expansion of China for the foreseeable future," said Cliff, a research engineer at the University of California, Davis.

He has monitoring stations on Mount Tamalpais, Donner Summit near Lake Tahoe, and Mount Lassen in far Northern California. Those sites see little pollution from local sources, and the composition of the dust particles matches that of the Gobi Desert and other Asian sites, Cliff said.

About a third of the Asian pollution is dust, which is increasing due to drought and deforestation, Cliff said. The rest is composed of sulfur, soot and trace metals from the burning of coal, diesel and other fossil fuels.

Cliff is studying whether transported particulate matter could affect climate by trapping heat, reflecting light or changing rainfall patterns.

Most air pollution in U.S. cities is generated locally, but that could change if citizens in China, India and other developing nations adopt American-style consumption patterns, researchers say.

"If they started driving cars and using electricity at the rate in the developed world, the amount of pollution they generate will increase many, many times," said Tony Van Curen, a UC Davis researcher who works with Cliff.

The U.S. Environmental Protection Agency estimates that on certain days nearly 25 percent of the particulate matter in the skies above Los Angeles can be traced to China. Some experts predict China could one day account for a third of all California's air pollution.

Dan Jaffe, an atmospheric scientist at the University of Washington, said he has detected ozone, carbon monoxide, mercury and particulate matter from Asia at monitoring sites on Mount Bachelor in Oregon and Cheeka Peak in Washington state.

"There is some amount of the pollution in the air we breathe coming from halfway around the world," Jaffe said. "There ultimately is no 'away.' There is no place where you can put away your pollution anymore."